Typically, a rotor blade for a wind turbine is made of a spar and, for example, two blade halves connected to the spar. Nowadays, wind turbines have large blades (e.g., with a length of about 50 m or more) which are made of, for example, a composite material.
From DE 10 2008 037 367 A1 it is known to segment such large blades and to manufacture and to transport the blade segments separately. The blade segments are joined at the wind turbine site, for example. An inner spar segment of an inner blade segment can be inserted partially into an outer spar segment of an outer blade segment and the inner and outer spar segments are adhered to each other.
A similar method is known from DE 10 2008 055 513 A1. A grid structure is provided at a spar segment of a blade segment to be inserted into another spar segment of another blade segment in order to improve the distribution of an adhesive and thereby to improve the adhesion of spar segments to each other.
Moreover, from EP 0 690 228 B1 it is known to adhere a blade spar and two blade belts together and to reinforce the connection by means of overlapping outer fiber layers impregnated with resin. Alternatively, pre-cured belts can be positioned in a blade half and the blade spar is adhered to the pre-cured belts by the final curing of the blade half together with the pre-cured belts.
Another method for manufacturing a blade on the basis of two or more blade segments is known from WO 2009/156061 A2. During the manufacturing of a segmented wind turbine blade at least two of the blade segments are interconnected in an integration device. In the integration device, at least one web and at least one belt may be further connected to the blade segments. The segments, webs and belts may be produced from fiber layers and resin. In a first step, the segments, webs and belts are pre-cured, and after pre-curing, they are adhered to each other for interconnection. Consecutively, the interconnection is cured.
Embodiments in accordance with aspects of the invention provide an improved method for manufacturing a segmented blade spar.